Re-setting the BIOS will clear all settings and make it default.. RTFM. :P ASUSTeK Computer Inc. -Support- Troubleshooting SABERTOOTH Z77 (there is a switch and 2 jumpers... Check the CLRCT_SW is enabled then you can just press the button on the back of the machine
You will need to (once it boots) go in and change settings like sata type to AHCI etc if you had them done before (AHCI is faster than IDE for your SSD)
Any OC settings will be cleared too.